Cyclic guanosine monophosphate (cGMP) is a key messenger molecule that links absorption of photons to neural signaling in the vertebrate photoreceptor. Naturally occurring mutations of the [unreadable]-subunit of PDE (PDE[unreadable]) gene in rods leads to rapid photoreceptor degeneration in rd mice. A new mouse model with PDE[unreadable] mutation, rd10 mouse, in which rod photoreceptor degeneration initiates at about P16, with only cone cell bodies remaining at P30, will be employed to test if in time correction of mutant gene can lead to long-term stable retinal rescue. This requires a very rapid onset of therapeutic genes, which is a challenge for conventional vectors. In side-by-side experiments we propose to test for therapy in the rd10 mouse using AAV vector and DNA nanoparticle (LPEI) approaches to retinal gene delivery, both separately and in combination. In addition we propose to test the Sleeping Beauty (SB) transposon system via the DNA/LPEI nanoparticle approach as a way to combine the advantages of both the vector and nanoparticle techniques in a single system. Specific Aim 1. Test the therapeutic efficacy of AAV delivered PDE[unreadable] in the rd10 mouse. Specific Aim 2. Test the therapeutic efficacy of DNA/LPEI nanoparticle delivered PDE[unreadable] in the rd10 mouse. Specific Aim 3. Test the therapeutic efficacy of combined AAV + DNA/LPEI nanoparticle delivered PDE[unreadable] in the rd10 mouse. Specific Aim 4. Test the therapeutic efficacy of Sleeping Beauty transposon DNA/LPEI nanoparticle delivered PDE[unreadable] in the rd10 mouse. Our overall aim is to determine by comparison of these four alternatives for retinal gene delivery which achieves the most effective and safest therapy in this challenging, rapid onset model of recessive RP. Our ultimate goal is to establish a retinal gene delivery system that is fast, of long duration and can accommodate large therapeutic cDNAs. Our overall aim is to determine which of four alternatives for retinal gene delivery of the PDE[unreadable] gene achieves the most effective and safest therapy in this challenging, rapid onset model of recessive RP, the rd10 mouse. Theses alternatives include AAV alone, DNA/LPEI nanoparticle alone, AAV combined with DNA/LPEI nanoparticle, and the Sleeping Beauty transposon DNA/LPEI nanoparticle. Our ultimate goal is to establish a retinal gene delivery system that is fast, of long duration and can accommodate large therapeutic cDNAs. [unreadable] [unreadable] [unreadable]